A man has been banned from standing near any woman he doesn’t know in public after sexually assaulting a 13-year-old girl in front of her family.
Abdulrizak Ali Hersi, 32, attacked the schoolgirl when she got onto a Tube in central London with her family.
Plain clothes police officers saw the incident and arrested him.
The assault happened just before 5pm on 11 October last year after Hersi boarded a train at Green Park Underground station.
He stood near the doors and at the next stop a family got on the Piccadily Line train.
Moments later, Hersi sexually assaulted the 13-year-old girl.
Officers on patrol who saw the attack unfold grabbed Hersi and dragged him off the train when it arrived at Leicester Square station, then arrested him.
Hersi, of Limehouse, east London, was jailed for 18 months after being found guilty of sexual assault at Inner London Crown Court on 5 May.
A judge also handed the defendant a 10-year Sexual Harm Prevention Order - banning him from "intentionally standing behind or next to any female he doesn’t know in a public place".
Hersi was also ordered to pay a victim surcharge of £187.
Inspector Sharon Turner, of the British Transport Police (BTP) said: “Our plain clothes teams are specially trained in identifying dangerous sexual offenders like Hersi, who will do their level best to commit such crimes without notice.
“In this case, the victim and her family didn’t even realise what was happening until our officers quickly intervened.
“Passengers should feel reassured to know we have plain clothes patrols like this taking place across the Underground day and night to keep everyone safe.”
Anyone with concerns while travelling on the Tube or on train can text BTP on 61016.